The primary research focus will be to examine arachidonic acid (ARA) metabolism of isolated platelets and neutrophils from normal individuals and patients with localized juvenile periodontitis (LJP). Emphasis will be placed on understanding how various periodontally relevant stimuli modify ARA metabolism in neutrophils and platelets and how neutrophil-platelet interactions regulate this process. ARA metabolism leading to thromboxane A2 and leukotriene B4 synthesis is critical for normal platelet and neutrophil function. The signals which are involved in triggering ARA metabolism and the molecular basis of the observed differences in LjP responses are not clearly understood and provide the focus of these studies. We also propose experiments to study the effects of platelets and products of stimulated platelets on neutrophil function. Neutrophil function tests will include chemotaxis and the phagocytosis and killing assay using Bacteroides gingivalis (Bg), Actinobacillus actinomycetemcomitans (Aa), Staphyloccus aureus and E. coli as test microbes for the latter two assays. By studying both Bg and Aa as representative periodontal pathogens, along with normal and LjP neutrophils and platelets in a model, we hope to provide insight into the role of ARA metabolism in periodontal diseases.